Simple wheel rotation question.
I have a wheel on screen with numbers. Something like wheel of fortune.
It''s divided into 32 areas (32 numbers) with same width of 11.25 degrees
It starts to spin at constant speed 8 degrees each 20 ms (that''s the timer time).
So it''s 400 degrees per second.
I need to slow it down in couple (let''s say X) of seconds and stop on specific number.
Let''s say i''m at number 18 right now and i need to slow it down and stop on number 3.
So the slowdown path will be 551,25 degrees ((32-18)+3+32).
32 is an extra 1 loop rotation for smoother stop
So now i need to find a number to decelerate the wheel each 20ms.
From 8 degrees per 20 ms to 0 degrees...
That has to do something with mechanics or angular rotation.
But it was long time ago so i can''t remember anything.
The problem is that I can change value only EACH 20 ms. Else I have the formula:
v^2 = u^2 + 2*a*s
u = initial velocity, v = velocity, a = acceleration, t = time, s = displacement (distance)
So it will be
0^2 = 400^2 + 2*a*551,25
But when it comes to slowing down only 50 times a second this thing doesn''t work because of non-uniform deceleration.
Here comes something like
s = u*t + 0.5a * t*t
But I can''t understand it.
If somebody can take a look here:
http://members.iglou.com/homepages/johnj/universetogalileo.html
and explain it to me...
Thanks in advance.
Just a Freak, emuFreak!
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